Pneumatic starting mechanism for automobiles.



C.L. WALKER.

PNEUMATIC STARTING MECHANISM FOR AUTOMOBILES.

I APPLICATION FILED SEPTJB. I916. ffififiBS. Patented De0.18,191?.

5 SHEETS-SHEET 1.

M WW

I ATTORNEYS C. L. WALKER. PNEUMATIC STARTING MECHANISM FOR AUTOMOBILES.

APPLICATION FILED SEPT. I8. I916.

Patented Dec. 18, 19W.

SHEETS-SHEET 2.

II III' I III IWIIIIIIIIIIIII CZZnionLJ Va life]? WITNESSE S:

C. L. WALKER. PNEUMATIC STARTING MECHANISM FOR AUTOMOBILES.

APPLICATION FILED SEPT. 1's. I916. 1,250,733. Patent-ed 1m18,1912.

' 5'SHEETS--SHEET 4.

INVENTOR Clin t0nZ/.Wa 11(9):

BY wig Arronnnzs c. L. WALKER. v PNEUMATIC STARTING MECHANISM FOR AUTOMOBILES.

Patentd. Dec. 18,1917.

5 SHEETS-SHEET 5.

APPLICATION FILED SEPT. I8, 1916- w 1 $5 I I k ilzkwl I -m- \i I II; @b a I w: A 1 Q A- L 77 2 $5 I 3 g II I 1 INVENTOR .'linibnlowalifen nvwfi on'inronrn. WALKER,, or .rxnmvi-onr, oA IroR-mm rnEU ATIo ST RTING MEC A SM on anrorxjoernnsz Toallwhom it may concern: Be it known that I, CLINTON L. 'YVaLKER, a citizen of the United States, res1d1ngat Piedmont, in. the county of Alameda. and

State. of California, have'invented new and useful Improvements in Pneumatic Starting Mechanism for Automobiles, ofwhich the following is a specification.

This. invention relates, to pneumatic. starters and pumps for use in starting internal combustion engines, and has for its object. to

simplify and. improve the construction and operation thereof. p I Although. not limited in use to anyparticular type of automobile, pneumatic startversfind their greatest use as an attachment at the. front. of the radiator. Necessarily the attachment .has to be located. at one side of the engine under such circumstances, and a driving belt or chain extended from the starter shaft'to the engine shaft. I provide a novel and adjustable connection. for securing the combined starterv and. pump in place on the engine at one side thereof, and employ a novel form of pump connection between the engine shaft and the chem drive leading to the starter shaft, whereby the chain drive may be disconnected when not in use, and allowedto remain 1dle. I make use. of a novel form. of cylinder andlpiston for the s'tarter'in order to obtain the greatest eliiciency in the limited space permitted. Novel and advantageous control and relief valve mechanism for the starter arealso. provided, and an advantageous arrangement is made use of in connection with the, check valve between the pump and storage tank whereby to obtainan oil seal aroundithe valve. Preferably I employ av single shaft. for both starter and pump, and therefore am enabled to. make. use. of one driving connection. be-

tween tliis. shaft. and the. engine. shaft. for

Specification of Letterslatent; Application. fua September 18,;1916.. Serial nolieogezi.

pump r, 1 Othjernovel and important features will become; apparent upon a. further understand- Patented Dec. 18 1,1917. I i

the andfor operating the ing-of the invention In. the, accompanyingdrawings, Figure 1 J showsgasideelevation of. the front portion of an automobile embodying my invention, certain parts. being broken away forlthe sake of. clearance.

Fig; 2-. shows an end View" of the supporting mechanism for the starter and pump-detachablyiconn'ectible with an automobile engine.

' Fig 3shows side elevation of .the same.

Fig. a showsa. vertical longitudinal'seo. 1.

. tional view through.- the pump illustrating .the starter .in" end elevation in. the background.

=. Fig. 5. shows as side -elevation oftheicom- ,bined starter and pump,

; Fig.6; shows a longitudinal. central sec tional view. through the starter-and pump,

v Fig. 7 shows. atransverse sectional view through the starter.

Fig, .8 shows a circumferential view through the: sprang hOllSlllg: of. the starter.

. Fig. 9 showsa. detailed'gsectional view. of the starter shaft illustrating the" ratchet clutch-mechanism Fig. 10 shows adetailed sectional view'of the starter illustrating a modified form: of

connection. betweenathe; piston and sleeve.-.-

F1g..1l shows a;deta1ledsectionah View of therehef. and check valve mechanism employedbetweenthe pumpa-nd storage tank.

Fig. 12 shows adetailed sectional view of the clutchconnect on on. the engme shaft. for receivlng the driving chamof the starter.

Figs..13 to l6inclusive show detailed views p of other parts of said clutch. mechanism.

171 is a fragmentary transverse section through; a slightly. .mo'difiedform; of. a

starter. in which. the-head is secured} between 1 the flangedendsof the cylindricalv sheet. p

Fig. 18 isafragmentany el'evationof. the

modified-starter. 1 In. Fig. I 1..Ixshow a portion of an autom bile including a radiator 10* and, internal combustionengine llh I 1 p v The.. starter; of... the; oscillating, piston,

- either side of the type as indicated generally at 12, the pump is of the type shown and described in my co-pending application Serial No. 46,057 filed Aug. 18th, 1915, and is indicated generally at 13, and these two are combined and detachably mounted upon one side of the engine.

The supports for the starter and pump comprise a frame 14, illustrated in end elevation in Fig. 2, and in side elevation in F ig. 3. I

The frame has lugs or arms 15, preferably two above. and one below, detachably 'secured to the side of the motor by means of bolts or screws 16. The arms 15 are so positioned that the upper ones register with the position of the cylinder head bolts, and the lower one registers with one of the bolts used for connecting the cylinders and upper half of the crank case in a Ford motor.

The frame 14 includes end pieces 17, having vertical slots 18 in which are slidably mounted blocks 19 and 19 connected to the starter and pump respectively, and adjustably supported by screws or bolts 20. By

a stationary part of the cylinder. Therefore manipulating the screws 20, the position of the starter and pump may be adjusted ver tically for the purpose of tensioning the driving chain as will hereinafter appear.

The starter comprises a casing 21 formed of a single sheet rolled into cylindrical form, with its ends 22 provided with flanges adapted to be secured together by means of screws or other clamping devices. Disk shaped members 23 and 23 form the end walls of the starter and are inserted .in grooves formed in the casing and securely held therein when the ends 22 are clamped together.

The end wall 23 it will be noted also forms one side of the pump 13, and is connected integrally therewith. A common shaft 24 is provided for both starter and pump, and is journaled at its ends in bushings 25 mounted in the end pieces 19 and 19 The starter has a piston 26 carried by a sleeve or hollow shaft 27, the latter rotatably supported in hubs 28 formed on the end walls of the starter. Cooperating with the piston is a longitudinally extending stationary head 29, which as shown in Fig. 7, is fitted in radial slots or grooves formed in the end walls of the cylinder, and carries a leather packing 30 on its front face, having itsends engaging the walls of the cylinder and turned toward the high pressure side. \Vood fillers 31 are bolted to head 29 and form bumpers for absorbing the shocks of the piston. The piston is also shown as supplied with a bumper 32 and a packing member 33. A

ring 34 of soft rubber is preferably mounted in the filler 32 for expanding the ends of the packing 33. If desired, stay bolts 35 may be extended longitudinally throughthe 'means of a cap 54 secured to the piston. This is a strong and extremely inexpensive connection, no special form of tool being required to construct 1t.

The clutch mechanism is interposed between the sleeve 27 and shaft 24 and comprises a fixed member 38 keyed to the shaft and a shiftable member 39 coarse threaded to the sleeve 27 and moved'longitudinally by a screw feed action. These clutch members have theircooperating faces provided with ratchet teeth. A drag spring 40 'as shown inFig. 9 is attached to a bushing 41 which latter is fixed upon a bearing ring'42 remo-vably secured to the head 23 This spring presses at its free end against the inside shoulder on the member 39, and forms a yielding and frictional connection between the screw feed clutch member and when the piston 26 is initially moved, the said clutch member will be restrained in its 'rotative movement, thereby allowing the The piston is automatically returnedby' 1 a clock spring 43 carried within an annular flange 44 on the exterior of the end-wall 23 and secured at its outer end thereto. "The inner end of the spring is secured to a hub 45 which is screw threaded to the adjacent end of the sleeve 27. Thebearing block 19 is detachably secured to the flange 44 and forms therewith an inclosed housing for the spring. The outer end of the spring is hooked in an opening formed in the peripheral flange of the bearing block member 19 so that the latter may be removed from' its vertical guide and turned over to vary the tension of said spring. A modified form of return spring is shown in connection with Fig. 10 and comprises a contractile coil spring 46, on the exterior of the housing, to which is attached a rope 4'7 wound upon a drum 48, the latter formed upon the hub 45.

The forward end of the shaft 24 has fixed upon it a sprocket wheel 49 carrying a chain 50 running to a sprocket wheel 51 on the crank shaft 52 of the motor.

shaftas to utilize the parts of a Ford motor to the greatest possible extent. As will be seen in Fig. 12, I provide an extension 53 for the crank shaft, and connect it thereto by secured by pins 55, the latter already being in place on the crank I so arrange the connect ons between the chain and crank renames shaft: for: connecting the fan drive pulle "side face of thecap 04 (see Figs. 12 16 inclusive) nismmay be provided for the-slidable mem- Any suitable-shifting mechaber 57 and the engagement shouldbe made ust as the englne 1s dy1ng"so as to'be m position for use in re-starting:

' The clutch pins 60 to I'BCBlVG the usual hand crank 61 w1ll be carried on the outer end of the extension 53. It will-be seen that this arrangementd'oesnot disturb-the alin'ement of the driving and driven sprocket wheels of the'chain drive, and'hasadvantages over frictional clinch/devices:- in economy of space and" constructiom The shiftablemeinber 57 is preferably provided with 8 pins and seven of said pins might bebroken off; and the clutch would still hold 'w-ith'the one remaining.

The operative connections for the starter and pump include a supply tankw62-connected by a pipe 63 with the exhaust valve ofthe air pump. Included in the pipe connections 63are stand pipes 64 and: 65 carrying respectively a relief valve 66and a check valve 67. As shown in Fig: 11 said stand pipes are of'a somewhat enlarged diameter and occupy a vertical position so that'oil which leaks from the pump 1 3 will be carried by the air through the pipe 63 andl be trapped in said stand pipes above the valves 66 and 67, thereby forming'oil seals for said valves to prevent leakage. i

From the supply tank 62* a pipe connection 68 is extended to the starter 12' and opens into the cylinder at apoint between the stationary head and piston. The control valve for the starter may belocat'ed adjacent thetank or on the starter.v In Fig. 5- I show it onthe starter and: it preferablycomprises a casing 69 having a removable cover 70 and inlet and discharge opening 71 and 72- respectively. The control valve has a double seat comprising apiston-73 fitted. in a restricted passage wayin the. casing, and a flanged head 74 with V shaped grooves on its under surface adaptedto seat-upon a fabric ring 75. valve into closed. position? A tubular extension 77. on the valve passesethrough the casing 69 and carries on its outer end a relief:valve 78 provided with a beveled head .7.9 to.seat against-the open end of the tubulare'xtensi'on. The tubular extension communicates with the outlet chamber 7 2 of the A spring 76 presses the sprocket Between the ends of the shaft'and the blocksvalvecasing throughgapertures 801 :For operating the control: and relief/valves I provide a;-lever 8l pivoted at 82 to the valve casing and having, a; foot extension 83.underlying the; head 7 9*of1 the relief valve and the extension 77 of' the controlling valve: The

. relief valve," is unseated' and rests uponthe extension 83 when the lever is released, whereas the control valveflsnormally seated by the'pressure vofmthespring 7 6.- A; pull upon the lever 8l will first-cause the relief valve't'oibe closedsand thereafter the control valve to be raised allowing air from the .tank 62 to rushinto the starting cylinder and movethe piston onerevolution. lVhen' the lever 81 is released the control valve is seated-by the spring? 6 and the relief valve drops back to openiposition by gravity or otherwise and allows the air present in the starter .to' be I exhausted;

*The-construction ofthe flanged head 74 and fabric ring 7 5 is such as to permit the use of an oil sea-l therefor, after the manner of the seals described" in connection with F ig. 1 1.. In Fig. l, .I. show the control and reliefx'ivalves "and operating mechanism "therefor, arranged adjacent the tank 62, l the construction and operationubeing the: same as that already described. a.

The pump in its essentials comprises a' chamber 84-oneither side-0f which is a 03 1 inder 85 in: alinement with each other and each fitted with a piston 86, the pistons'being operated by an" eccentric disk 87 mounted upon a squared portion 0f=the shaft 24:; 'By' combining the pump and starterin one unit and mounting both on a single shaft, I am enabled tosimplify the driving connections with the crank shaft. The pump may be operated while the 'engine is runmng by throwing the clutch member 57 into engagement, and by reason ofthe ratchet clutch between the sleeve 27 and shaft 24', the starter piston -26 will remain; idle. When sufficient air has been pumped into the tank 62 the clutch member-57 is released and'the chain 50 andits sprocket wheels will remain idle'unt-il used again for starting the motor.

Various changes in the construction and arrangement of the several parts herein shown-and described may be made, without departing from the spirit of my invention as disclosed'in-the appended claims."

By splining the clutch .member 38- to the shaft 2% and mounting the-eccentric disk 87" on=a= squared por'tion'thereof; the said shaft is capable oflongitudinal adjustment in its hearings, to permit the alinement of the wheelsof the driving chain 50.

19* and 19 I interposeremovable washers As shown in ends 22 of the cylinder may have washers leaving the interior of the cylinder onthe low pressure side of the head 29 in communication with the atmosphere"; thus when the piston is moved to the limit of its power.

stroke, there is no tendency for the air to be compressed ahead of it, and also on the return stroke the tendency of a vacuum tobe created is overcome.

Also as shown in said modification, the head 26 may be extended between the spaced ends 22 and receive support therefrom, thus doing away with the necessity for stay rods or other supports.

Having thus described my invention, what I claim and desireto secure by Letters Patent is e 1. In a pneumatic starting mechanism, in combination a cylinder having its body formed of a single sheet rolled into circular form with the ends of said sheet turned outwardly into opposing flanges, means adjustably connecting the flanges, said cylinder being formed with a seat adjacent each end, a head engaged in each seat and held therein by tightening upon said flange connecting means, and a piston operable in the cylinder.

2. In a pneumatic starting mechanism, in combination a cylinder having its body formed of a single sheet rolled into circular form with the ends of said sheet turned outwardly into opposing flanges, means adjustably connecting the flanges, said cylinder being formed with a seat adjacent each end, a head engaged in each seat and held therein by tightening upon said flange connecting means, each head having a center shaft bearing, a shaft journaled in said bearings, and a piston carried by the shaft within thetcylinder, said shaft serving as a sustaining, spacer between said heads.

In a pneumatic starting mechanism, in combination a. cylinder having its body formed of a single sheet rolled into circular form with the ends of said sheet turned outwardly into opposing flanges, means adjustably connecting the flanges, said cylinder being formed with a seat adjacent each end, a head engaged in each seat and held therein by tightening upon said flange connecting means, each head having a hub extension, a sleeve journaled in the hubs, a piston carried by the sleeve within the cylinder, a shaft passing through the sleeve, a gear fixed on the shaft for connection with an engine shaft, and clutch mechanism interposed between the sleeve and the first shaft.

4. In a pneumatic starting mechanism, in combination a cylinder having its body formed of a single sheet rolled into circular form with the ends of said sheet turned outjustably connecting the flanges,

on the shaft within the sleeve, a cooperating clutch part threaded interiorly of the sleeve for advancing toward and retracting from the fixed clutch part, and a drag spring interposed between the second clutch part 1 and the shaft.

5. In a pneumatic starting mechanism, in combination a cylinder 7 having. its body formed of a .single sheet rolled into circular form with the ends of said sheet turned outwardly into opposing flanges, means adjustably connecting the flanges, said cylinder being formed with a seat adjacent each end, a headengaged in: each seat and held therein by tightening upon said flange connecting .1

means, eachhead having a hub extension, a

sleeve journaled in the hubs, a piston-can ried by the sleeve within the cylinder, a shaft passing through the sleeve andextending therefrom at its ends, a connection between the shaft and sleeve, and adjustable bearings for the projecting ends of the shaft.

6. In a pneumatic starting mechanism,in combination, a cylinder having its 'body formed of a single sheet rolled into circular form with the ends of said sheet turned outwardly into opposing flanges, means adsaid cylinder being formed with a seatadjacent each end, a head engaged in each seat and held therein by tightening upon said flange connecting means, each head having a hub extension, a sleeve journaled in the hubs, a piston carried by the sleeve within the cylinder, a

shaft passing through the sleeve, means releasably connecting the sleeve to the shaft, a hub extending from the sleeve through. the hub extension of the adjacent head, and spring means secured to the hub exterior of the cylinder for returning the piston to its normal position,

7. A pneumatic starter and pump having a shaft common to both, a support for said starter and pump adapted to 'be'secured to one side of an internal combustion engine, a chain drive for the shaft adapted to connect the latter to the engine shaft, and means by which said first shaft may be disposed at longitudinally fixed adjustments to permit alinement of the chain driving connections.

8. In a pneumatic starter, in combination, a cylinder, a shaft longitudinally adjustable therein, a hollow shaft arranged within the gear fixed on the shaft, a clutch part fixed tater-3e,

cylinder and; about 1 the first shaft, a piston carried; by 'the hollow shaft ithin the cylinder, anda drag spring-interposed between the two shafts for frictionally connectingthe-same on rotary movement-of one of sal shafts. v W

9; I A); pneumatlc starter comprising a 5 eye lindrical body-portion-formed of one piece, longitudinally extending and having flanged ends, detachably connected together and end- Wallsreceived in grooves in said body por I lindrical body portion formed of one tion 7 and held therein by the clamping, ac tion ofs'ai o rp t n-fl 10. A pneumat c starter compr sing a cylindricalibody llOl-tlQlLfQI'II-Ed of one'piece,

and having flanged longitudinally extending ends detach bly connected together, end-.

WflllSIBCBIlVGCl in grooves insaid body portion and held therein by theclampingaction of said body portion, a stationary-head in said'cylinder extending radially, a shaft ex;

tending longitudinally through the cylinder a sl'eeveon said shaft, a piston fixed upon said sleeve,and connecting means interposed between said f sleeve and shaft.

ll. A pneumaticstarter comprising a cye piece and having; flanged longitudinally extendin'g ends detachably connectedtogether, Wallsreceived in groovesln 331d body; portion; and'held therein by theiclamping ac a stationary head tion of said body portion,

a shaft in said cylinder extending radially,

extending longitudinally through the cylin-v fi ed upon said sleeve, and means interposed he; 7

and having flanged longitudinally; extendingend-s. detachably connected together, end- Walls received in grooves in said body por- ,tiorr and held, therein-by, the clamping ac'-,

tion of; said body portion, and a pump formed integrally with one end-Wallof said starte-n. r

13'. In a pneumatic starting mechanism,

, in; combination, a cylinder having-its body.

' being formed formed of a single sheet. rolled intocircu lar. form with the-endsofsaid sheet turned outwardly into :opposing' flanges, means ad; said cylinder justably, connecting the flanges,

Witha seat adjacent each end, a headengagedzin-each seat and held'therein bytightening upon sa d flange connecting;

means, each head having a; hub extension, a sleeve" ournaled in the-hubs, a piston carried by, the sleeve Withinthe cylinder, passingthroughx the sleeve, one head having an exterior annular flange, bearings for-thev shat-tone of whichi isformed with; a Wall end? 7 fe l e an fixed upon the; shaft j ashaftaving-vanr am u ar, angei les opie l y e: lated totthe head flange, and forming therewith adiousing, and means arranged intheg;

housing thus formed for returning the pis; 1

ton to normal position. v.

14. In 1 a i pneumatic; starting 7 mechanism,

in combinat on, a1 cylinder having its;body

formedof a single sheet rolled into circular form. With the ends of said sheet turned outn I a sleeve journaled in thehubs, a piston carried the sleeve Within the cylinder, a; shaft pass ng through the sleeve, aclutchvpart in-; terposed between thefsleeve and shaft andslidably connected to one, a, cooperating clutchpart threadedly connected to, the other" Wardlyinto opposing flanges, means adjust.- ably connecting the flanges, said cylinder; being formed \vitha seat adjacent each end, a head engaged in each seat and ,held therein}- by, tightening upon said flange connecting means," each head having ahub extension,"

ofsaid two lastnamed elements foradva-nce a menttoward and I retraction from the first clutch part, ahub fiXedon thesleeve in the;

path of the slidable clutch partvand extend mg throughthe hub extension of, the adjacent. head,- and' means connected with the hubfor returning-the piston to normal position.

15. In a pneumatic starter, incombina-.

tion, aicylinder, a shaft longtiudin ally adjustable therein, a hollow, shaftarranged Within the cylinder and aboutthe first shaft,

a piston carried by the hollow shaft Within-v the ;cylinder,; a drag spring interposed bes tween the two shafts for clutching'the same. together upon rotation of the hollow shaft; Qne direct ve lvi an an f urm g the. h ll ha t e Q -l P sitio s, 1

16- a; P umat tar ng m c a sm; ns m nat n, y inder. havi e emov b heads; each formed With'a center bearing, ai piston-rotatably supported within the cylin}; @161: a an in he ar n a' me nsf r return ng the, piston to normal position, a housing; for said means carried by: one head, a-pump having its casing carried by the other head,

and a, shaft extending through the cylinder, housmg and pump casing for; operating-the pump and being operated by-the pie; I

ton. a

17. In ,a pneumatic starting. mechanism,

in combination a cylinder having removable heads eachzfor-med with a centerbear-ing, a PlStQn rotatably supported within the cy1-. inder and in the bearings, means for return t e p t n o alp itiom s ng for saidmeans carried by one. head, a pump having its casing carried by the othermhead;

shaft extending through the-. cylinder, L

qusi g, a pump sing;forope at ngmea pump and: being operated-by, the? piston, shaft bearings carried by the housing and pump;- asing a s pnqr lting-- frame havin guideways in which the shaft bearings are slidably arranged, and means for adjusting the shaft hearings in the guideways of the frame.

18. In an oscillatory pneumatic starter,

- in combination, a cylinderhaving its body formed of a single sheet rolled into circular form, with the ends of said sheet connected together along their longitudinal edges and spaced apart to permit free communication with the atmosphere a head arranged within the cylinder atone side of said spaced ends, and apiston movable in the cylinder and having its low pressure side exposed toward said spaced ends.

'19. In an oscillatory pneumatic starter, in combination, a cylinder, a shaft extending therethrough, bearings for said shaft whereby to support the cylinder, a driving gear fixed to one end of said shaft for 0perative connection with an engine, a sleeve on said shaft within the cylinder, a friction clutch between the sleeve and shaft adapted to engage the latter at any point throughout its length and thereby permit the shaft to be moved longitudinally relative to the cylinder whereby to aline the driving gear thereon with respect to a gear on the engine shaft, and a piston fixed to the sleeve for operation in the cylinder.

20. In an oscillatory pneumatic starter, in

combination, a cylinder, a shaft extending therethrough, bearings for said shaft whereby to support the cylinder, a driving gear fixed to one end of said shaft for operative connection with an engine, a sleeve On said shaft within the cylinder, a clutch between the sleeve and shaft adapted to permit the shaft to be moved longitudinally relative to the cylinder whereby to aline the driving gear thereon with respect to its connection with the engine shaft, and a pump carried also on said shaft and having its piston operatively connected therewith, said con nection being such as to permit relative end-' Wise movement of the shaft.

21. In an oscillatory pneumatic starter, in combination, a cylinder having its body portion formed of a single sheet rolled into circular form, the ends of said sheet being flanged and connected together along their longitudinal edges, a piston for said cylinder and a stationary head carried in said cylinder and extending between the flanged ends of said body portion and supported thereby.

22. In an oscillatory pneumatic starter, in combination, a cylinder having its body por tion formed of a single sheet rolled into circular form, the ends of said sheet being flanged and connected together along their longitudinal edges, a piston for said cylinder and a stationary head earned in said cylinder and extending between the flanged ends of said body 'portionand supported f thereby, and disk shaped end walls'for said cylinder clamping against the ends of said stationary head.

23. In a pneumatic startlng mechanism, in combination, a cylinder formed of a sheet of metal rolled into'circular form with the H ends of said sheet outturned into oppos ng 1 flanges, end walls for the cylinder, a stat onary head secured between the flanges of the cylinder in spaced relation to one thereof to provide an outlet, and a piston rotatably j mounted in the cylinder; and normally con tacting with the head, said cylinder being formed with'a peripheral inlet opening dis posed in radial alinement with the contacting faces of the piston and head. r

2-4. In a pneumatic starting mechanism, in]

combination, a cylinder formed of a sheet of metal rolled into circular form with the ends of said sheet outturned into opposing flanges, spacing means secured between the flanges to hold the latterapart' and thereby provide for the escape of air in advance of I the iston, end walls for the c linder a sta-' L 7 tionary head fixed between flanges and arranged in the cylinder, and a pistonrotatably mounted in the cylinder contacting with the head.

25. In a pneumatic starting mechanism, in combination, a cylinder having 1ts body and normally formed of a. single sheet rolled into circular form with the ends of said sheet turned outwardly into opposing flanges, means adjustably connecting the flanges, said cylinder beingformed w1th a seat ad acent each end, a head engaged in each seat and held there in by tightening upon said flange connecting means, each head having a hub extension, a

sleeve journaled in the hubs, a piston carried by the sleeve within the cylinder, a shaft passing through the sleeve, a clutch part interposed between the sleeve and shaft and slidably connected to one, a cooperatingclutch part threadedly connected to the other of said two last named elements for advancement toward and retraction from the first clutch part, a gear fixed on the shaft for connecting the latter to the shaft of an engine, and means for sliding the first shaft relative tothe clutch parts for adjusting the position of the gear.

26. In a pneumatic starter, in combinashaft extending through the cylinderfor operating the pump, and means connecting the piston to the shaft.

7 27. In a pneumatic starting mechanism, in

through one end wall, a piston carried by said shaft for operating with the casing, a

second shaft arranged within the first shaft and having an end projecting from the hub extension, a movably supported journal block in which the projecting end of the second shaft is supported, said journal block having a perforated cylindrical flange encircling the hub extension, and a coiled spring for returning the piston to normal position having hooked terminals engaging respectively in the perforations of the hub extension and block flange, said journal block adapted for being turned to vary the tension of the spring.

28. In a pneumatic starting mechanism, in combination, a casing, end walls therefor having bearings, one end wall having an annular flange, a sleeve-like shaft journaled in the end wall bearings and having a perforated hub extension projecting through said specified end wall, a piston carried by said shaft for operating with the casing, a second shaft arranged within the first shaft and having an end projecting from the hub extension, a movably supported journal block in which the projecting end of the second shaft is supported, said journal block having a perforated cylindrical flange encircling the hub extension and telescopically related with the end Wall flange, and a coiled spring for returning the piston to normal position having hooked terminals engaging respectively in the perforations of the hub extension and block flange, said journal block adapted for being turned to vary the tension of the spring, and means detachably securing the telescoped flanges together.

29. In a pneumatic starter, in combination, a cylinder, end walls therefor having hub extensions, a hollow shaft journaled in the latter, a piston carried by the shaft, a

driven shaft extending through the hollow shaft and unsupported thereby, means releasably connecting the shafts, and journal bearings for the wardly of the hollow shaft.

30. In a pneumatic starter, tion, a cylinder, hub extensions, a hollow. shaft journaled in the latter, a piston, a radial series of rods carried by the shaft, headed bolts interposed between the rods and attached to the piston for clamping the rods to the piston beneath the bolt heads, a driven shaft extendin through the hollow shaft and unsupported thereby, means releasably connecting the shafts, and journal bearings for the driven shaft arranged outwardly of the hollow shaft.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

CLINTON L. WVALKER.

Witnesses:

JOHN H. HERRING, D. B. RICHARDS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.

driven shaft arranged outin combina-' end walls therefor having 

